Stewart (Moon)

Named after John Quincy Stewart - American astrophysicist (1894-1972).

Stewart is a small lunar impact crater that lies to the northeast of the Mare Spumans, a small lunar mare near the eastern limb. Stewart was previously designated Dubyago Q before being named by the IAU. This is a circular crater with a low outer rim and a level, featureless interior floor. (wikipedia entry)

A crater is a circular depression likely created by an impact event. On the Moon they are named after deceased scientists, polar explorers, astronauts or cosmonauts.